| Autor: |
Soos, Z. G., Kuwajima, S., Harding, R. H. |
| Předmět: |
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| Zdroj: |
Journal of Chemical Physics; 7/1/1986, Vol. 85 Issue 1, p601, 10p |
| Abstrakt: |
Diagrammatic valence bond (DVB) theory is applied to charge–transfer (CT) excitations in ion–radical organic solids that, like TTF–chloranil, are close to the neutral–ionic (n–i) interface. Small but finite Mulliken integrals |t| in mixed regular donor–acceptor stacks lead to charge resonance among segments containing 2r adjacent ions and to a linear lowering of the CT absorption. Finite t and long range Coulomb interactions also lead, up to a critical value, to an ionicity jump Δq=qi-qn <1 between the neutral and ionic phases. The TTF–chloranil ionicities and CT absorption are fit with |t|=0.23 eV. Neither attractive nor repulsive interstrand Coulomb interactions affect the CT spectra at fixed ionicity in the mean field approximation. Direct DVB solutions to finite (2N≤18) donor–acceptor strands yield the n–i interface while 2N≤16 strands suffice for the CT absorption and intensity. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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